I bought one of these back in '07 and was surprised to see it still available. The only reason I was looking to replace it was the age and wear on my old helmet. Living in Texas where heat is a nearly a year-round concern, I really like the ventilation and solid design. I've had lower speed mountain bike crashes and have always been protected. You can pay more for a helmet, but this is in the sweet spot of having great ventilation and solid design, not be a "one size fits all" but still be in a value price range. Cheaper helmets I've seen are not well ventilated and generally fit less well. I also bought one for my thrill seeking daughter.

i have about a 7.25 head. bought the large but was too big and quite bulky. it was huge on my head. kept it for winter riding with a liner under it. then got the medium which fits well when adjusted all the way out and is not as bulky.

I recently had to replace some recalled helmets that I really liked. I bought a couple Bell models knowing that Bells used to fit my head shape. I found the Delirium to be a nice helmet for the price. The length to width fits my long oval head shape well and still has room to fit over a cap on cold days. The visor comes in handy on morning and evening road rides to block the low angled sun.

I have had this helmet for 4 years, good fit, and why would anyone want to ride without the visor it comes with? The fabric on the pds comes loose as I sweat buckets in the Texas heat but just glue it overnight with some elmer's glue and I am back riding. I ride with a headsweats du-rag to ensure smug fit, protect pads from sweat. Because of the large vents I am able to run a cable through the helmet which I also run trough my front wheel then secure with my U-lock when I go shopping.